Apparatus for removing an elongated structure implanted in biological tissue

ABSTRACT

Disclosed is a lead removal apparatus for removing an implanted pacemaker or defibrillator lead from the heart. The lead removal apparatus includes a proximal handle that further includes a proximal portion, such as an elongate section of intertwined wire, having a compact, pre-formed first configuration, such as one or more coiled loops. The compact shape permits the operator to utilize the proximal portion without requiring the assistance of a second person to help keep it within the sterile field during a procedure. The operator is thus able to constrain or uncoil the proximal portion into a second configuration that is sufficiently straight such that a medical device, such as a dilator sheath, can be advanced thereover to help separate the lead from scar tissue along the vein path. The proximal portion may include sufficient resiliency to substantially return to the first configuration once the sheath has been advanced.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of provisional applicationSerial No. 60/204,652, filed May 17, 2000.

TECHNICAL FIELD

[0002] This invention relates to elongated structures, such as acatheter implanted in tissue or an electrical pacemaker or defibrillatorlead implanted in or on the heart and, particularly, to apparatus forremoving such elongated structures implanted in biological tissue.

BACKGROUND OF THE INVENTION

[0003] A heart pacemaker is generally implanted subcutaneously in thechest wall along with a coiled structure such as an electrical wire coillead for conducting electrical signals such as stimulating and sensingsignals between the pacemaker and the heart. The lead is surgicallyimplanted through a vein leading to a cavity of the heart. A typicallead includes one or more helical wire coils having a hollow innerpassageway that extends the entire length of the wire coil. The coiledstructures are positioned in the lead either coaxially or laterally. Thewire coils are surrounded by an insulating material such as a flexibletube, sheath, or coating comprising, for example, silicone orpolyurethane for insulating the wire coils from body fluids as well aseach other. However, one problem is that, over time, fibrotic tissuecommonly encapsulates the pacemaker lead especially in areas where thereis low velocity blood flow. When small diameter veins through which thelead passes become occluded with fibrotic tissue, separating the leadfrom the vein is difficult and causes severe damage or destruction ofthe vein. Furthermore, the separation is usually not possible withoutrestricting or containing the movement of the pacemaker lead.

[0004] In most cases, the useful life of a pacemaker lead lasts for manyyears. However, should the pacemaker lead become inoperative or shouldanother heart lead be desired, the existing pacemaker lead is typicallyleft in place, and a new pacemaker lead is implanted. One problem withleaving an implanted lead in place, particularly in the heart, is thatthe lead actually restricts the operation of the various heart valvesthrough which the lead passes. If several leads passing through a heartvalve are left in place, the operation of the heart valve and theefficacy of the heart is significantly impaired.

[0005] Another problem associated with leaving a pacemaker lead inplace, particularly in blood vessels, is that an infection may developin or around the lead, thereby requiring surgical removal. Surgicalremoval of the lead from the heart often involves open heart surgerywith accompanying complications, risks, and significant cost.

[0006] One method for transvenous removal of a pacemaker lead involves aprior art heart lead removal tool that utilizes a hollow, rigid tube anda beveled rod tip for engaging and deforming the coiled structure of theheart lead. However, when the lead cannot be removed because of somecomplication, a serious problem is that the tip of the tool is locked inplace and cannot be removed from the lead. As a result, the tool andlead must be surgically removed. Furthermore, the rigid tube of the toolcan easily puncture a blood vessel or, even worse, a heart cavity wall.

[0007] Another method is to transvenously extract the lead manuallywithout the aid of a tool. Such method is possible only when the leadhas not been encapsulated in or restricted by a blood vessel. Even then,this method has a number of problems. First, when the polyurethane orsilicon insulation surrounding the wire coil is damaged, the insulationcan sever and cause the coiled structure of the lead to unwind andpossibly to damage the heart and surrounding blood vessels. Secondly,when both the coiled structure and insulation are severed in the heartor a blood vessel, surgical removal is required. Thirdly, most pacemakerleads typically include tines or a corkscrew at the tip or a conicallyshaped tip for securing the distal end of the pacemaker lead to a heartcavity wall. For fibrotic tissue that has encapsulated the tip, unaidedmanual removal of the heart lead from the heart cavity wall may cause aninward extension or inversion of the wall, or even worse, permanentdamage to the heart such as tearing a hole in the heart cavity wall.

[0008] There a several different systems for lead removal that involvedadvancing a stylet into the coiled electrode and securing the electrodenear the tip of the lead to facilitate its removal. The LEAD EXTRACTION™System (Cook Vascular Inc., Leechburg, Pa., described U.S. Pat. No.4,988,347, entitled “Method and Apparatus for Separating a CoiledStructure from Biological Tissue”, Filed Nov. 9, 1988, and relatedsubsequent patents) is particularly well-suited for the removal of apacemaker lead implanted in the heart and encapsulated in vesselsconnecting with the heart. Others devices by Vascomed and Spectraneticshave entered the market in the U.S. and/or Europe. While the use of aradially expandable wire coil at the distal end of a stylet is aneffective method of securing the pacemaker lead near the electrode tip,failure to engage has been observed in a number of cases. In anexpandable wire coil system, correct sizing of the lead coil is criticalprior to introduction of the locking stylet. Nevertheless, behavior ofthe wire coil during expansion can be unpredictable so that even whenthe correct locking stylet is selected, adequate engagement with thelead coil often cannot be achieved, or the two can separate duringtraction to free the lead. While often this may occur due to improperlocking technique on the part of the physician, often the failure ispurely mechanical. Many times, a second locking stylet can be usedsuccessfully, but this results in increased material costs and risk tothe patient due to the lengthening of the procedure.

[0009] Another disadvantage of currently available systems is that arrayof different sized stylets must be used for the wide range of pacemakerelectrode sizes, normally 0.016 to 0.032″. Having to properly size thecoil for selection of the optimal stylet adds time, cost, and thepotential for error to the procedure. What is needed is a single lockingstylet that can expand to engage and remove any standard pacemaker lead,regardless of the electrode coil size.

SUMMARY OF THE INVENTION

[0010] The foregoing problems are solved and a technical advance isachieved with illustrative lead removal apparatus for removing animplanted, cardiac pacemaker lead. The pacemaker lead includes, aspreviously suggested, a coiled structure such as an electrical wire coilfor conducting electrical signals between the pacemaker and the heart.This coiled structure typically has a hollow inner passageway thatextends longitudinally therethrough. The wire coil is surrounded byinsulating material for insulating the wires from body fluids. The leadremoval apparatus includes control means having a distal end forinsertion into the passageway of the coiled structure. The lead removalapparatus also includes expandable means positioned proximate the distalend of the control means. The expandable means also has an expandedposition in the coiled structure passageway for securing the controlmeans to the coiled structure for removal of the implanted lead from theheart.

[0011] In one aspect, the control means comprises actuator means forexpanding the expandable means to the expanded position when theexpandable means is positioned in the passageway of the coiledstructure. The expandable means also includes a relaxed position forpositioning the lead removal apparatus in the coiled structurepassageway.

[0012] In another aspect, the control means includes an outer tube andan actuator rod insertable through the outer tube. The expandable meansincludes a barb positioned proximate the distal end of the outer tube.When the actuator rod is positioned proximate the distal end of theouter tube, the rod expands the barb to the expanded position.

[0013] In another aspect, the expandable means includes a slotted sleevepositioned between the distal ends of the outer tube and the actuatorrod. The ends of the tube and rod engage the slotted sleeve whenexpanding the slotted sleeve to an expanded position, which hooks intothe coiled structure for securing the actuator rod to the coiledstructure. The distal ends of the rod and the outer tube are beveled foreasing expansion of the slotted sleeve when the actuator rod iswithdrawn from the outer tube.

[0014] In still another aspect, the expandable means includes anexpandable pliable material sleeve between the distal ends of the outertube and the actuator rod. The pliable material sleeve comprises, forexample, a pliable material such as synthetic rubber and the like, whichexpands in a radial direction when compressed between the distal ends ofthe outer tube and the actuator rod to frictionally engage the coiledstructure and secure the outer tube and actuator rod thereto. In anotherconfiguration, the pliable material sleeve has an outside dimensiongreater than the coiled structure passageway when the sleeve is in arelaxed position. The sleeve is stretched between the distal ends of theouter tube and actuator rod to reduce its outer diameter, which is theninsertable into the coiled structure passageway.

[0015] In yet another aspect, the expandable means of the lead removalapparatus includes projection means proximate a distal end of the outertube for hooking into the coiled structure. The control means furtherincludes a stylet for engaging and urging the projection means into thecoiled structure when positioned in the coiled structure passageway.

[0016] The lead removal apparatus may also be characterized ascomprising tube means having a distal end for inserting into thepassageway of the coiled structure, expansion means positioned proximatea distal end of the tube means for hooking into the coiled structure ofthe pacemaker lead; and stylet means insertable into the tube means forengaging the expansion means. As previously suggested, the tube meansincludes an outer tube having a passageway extending longitudinallytherethrough. The stylet means includes a wire extending through theouter tube passageway. And the expansion means includes a projectionproximate the distal end of the outer tube hooking into the coiledstructure when positioned in the coiled structure and expanded outwardlyfrom the outer tube.

[0017] The lead removal apparatus may also be characterized ascomprising an outer tube having a passageway extending longitudinallytherethrough, which is sized for insertion into the passageway of thecoiled structure; an anchoring projection positioned proximal the distalend of the outer tube; and a stylet positioned through the outer tubepassageway and urging the anchoring projections between relaxed andhooked positions. In the hooked position, the anchoring projectionextends outwardly from the outer tube and when also positioned in thecoiled structure passageway hooks into the coiled structure. In therelaxed position, the anchoring projection is insertable into the coiledstructure passageway for positioning therein.

[0018] The foregoing problems are also solved and a technical advance isachieved with illustrative apparatus for removing an elongated structuresuch as a catheter or an electrical pacemaker lead implanted inbiological tissue such as a blood vessel or a heart cavity wall. Theillustrative apparatus includes a control unit having a longitudinalpassageway such as a flexible tube that is insertable in thelongitudinal passageway of the catheter or the wire coil of thepacemaker lead for controlling movement of the elongated structure.Positioned about the distal end of the control unit is an expandableunit that is operable to a position for securing the control unit to theelongated structure. The control unit passageway is used for operatingthe expandable unit.

[0019] In a first embodiment, the control unit is a flexible tube withone or more side ports or apertures for passing a fluid therethrough foroperating the expandable unit. In this embodiment, the expandable unitis a balloon attached about the distal end of the tube with the sideports leading from the passageway for inflating or expanding the balloonto an expanded position for securing the control unit to the elongatedstructure.

[0020] In a second embodiment, the control unit again includes aflexible tube. The expandable unit includes a number of twisted radialprojections each having a free end that is formed from radial strips cutin the distal end of the tube. The strips are twisted at the free endand pushed into the passageway of the tube. The apparatus furthercomprises an actuator such as a rod that is inserted into the passagewayof the tube to engage and expand the free end of the projections intothe wire coil of the pacemaker lead, thereby securing the control tubeto the wire coil.

[0021] In a third embodiment, a plurality of expandable strips arelongitudinally formed in the distal end of the control tube. Theactuating rod of the apparatus is inserted in the tube passageway andattached at the distal end of the tube. When the apparatus is insertedin the passageway of the elongated structure, the actuator rod is pulledin a direction out of the tube while operating the deformable stripsinto an expanded position engaging the wall of the structure passagewayfor securing the control tube to the elongated structure.

[0022] In a fourth embodiment, a number of barbs or a helical ridge isformed at the end of the control tube. The expandable distal end of thecontrol tube is partially collapsed or formed such that the barbs orridge when expanded by an actuator rod extend beyond the nominaldiameter of the tube. The actuator rod is extended through the tubepassageway to expand the distal end of the tube and cause the barbs orridge to engage the structure and secure the control tube thereto.

[0023] In a fifth embodiment, the apparatus also includes a hollowcontrol tube having a longitudinal passageway therein. An expandableslotted sleeve is positioned at the distal end of the control tube. Anactuator rod is inserted through the slotted sleeve and control tube.The distal end of the rod is enlarged to engage and expand the slottedsleeve against the distal end of the control tube. When inserted in thepassageway of the elongated structure, the actuator rod is pulled in adirection out of the control tube passageway to force the enlargeddistal end of the rod into the passageway of the slotted sleeve andexpand the slotted sleeve into the wall of the elongated structure. As aresult, the control tube is secured to the elongated structure forcontrolling the movement thereof.

[0024] In sixth and seventh illustrative embodiments similar in functionto the fifth embodiment, an expandable sleeve comprising a pliablematerial is positioned between the distal ends of the control tube andactuating rod. In the sixth embodiment, the pliable material sleeve iscompressed between the distal ends of the control tube and actuator rodto expand and engage the passageway walls of the elongated structure. Inthe seventh embodiment, the pliable material sleeve is already in anexpanded position to engage the passageway walls of the elongatedstructure. To insert this expanded pliable material sleeve into thepassageway of the elongated structure, the actuator rod is pushed intothe passageway of the control tube to longitudinally stretch the pliablematerial sleeve. As a result, the outside diameter of the sleeve iscompressed to allow the apparatus to be inserted into the passageway ofthe elongated structure. When inserted, the actuator rod is releasedallowing the sleeve to radially expand and engage the wire coil orpassageway walls of the elongated structure.

[0025] The invention is further directed to removal apparatus having aguide that is insertable into the passageway of the elongated structurefor guiding the control unit in the passageway. In those instances wherethe passageway of the elongated structure has become blocked oroccluded, the apparatus advantageously includes this guide for breakingthrough the occlusion. Furthermore, various diameter guides are insertedinto the structure passageway for determining the minimum passagewaydiameter of the structure when the structure has in some way beendeformed or damaged. Illustratively, the guide includes a stylet wirethat is first inserted into the passageway of the elongated structure.When the stylet guide has been inserted, the control tube is insertedover the proximal end of the stylet wire and inserted into thepassageway of the structure. In one embodiment, the expandable unit ofthe apparatus includes a wire coil positioned around and attached at itsdistal end to the control tube. When inserted, the control tube isrotated to expand the wire coil and secure the control tube to theelongated structure.

[0026] In another embodiment, the expandable unit includes a balloonattached about the distal end of the control tube. The control tubeincludes a second passageway that leads to the balloon for inflating theballoon to secure the control tube to the passageway wall of theelongated structure.

[0027] The invention is also directed to a removal apparatus having arotatable unit for securing the control unit to the elongated structure.In one illustrative embodiment, the removal apparatus includes a controltube insertable into the passageway of the elongated structure forcontrolling the movement thereof. Positioned about the distal end of thecontrol tube is a rotatable unit such as a cylindrical rod that isrotatable to a position off-centered from the tube for securing thecontrol tube to the elongated structure. The apparatus also includes anactuator rod extending through the control tube and attachedoff-centered to the cylindrical rod for rotating the rod into theoff-centered position securing the control tube to the structure.

[0028] The invention is still further directed to removal apparatushaving a control tube that is insertable into the passageway of theelongated structure and has an extended projection at the distal endthereof for securing the tube to the structure. Also included is astylet that is insertable into the passageway of the tube for operatingthe extended projection to a retracted position for insertion or removalof the control tube from the passageway of the elongated structure.

[0029] The invention also includes apparatus for separating theelongated structure from tissue that is restricting the movement and,consequently, the removal of the elongated structure. In oneillustrative embodiment, the separating apparatus includes a tube havinga first passageway for receiving the elongated structure. Positionedabout the distal end of the tube is a balloon that is inflatable forseparating restricting tissue from a length of the elongated structure.A second passageway extending along the tube and to the balloon isincluded for inflating the balloon.

[0030] In another embodiment, the separating apparatus includes a firsttube having a passageway for receiving the elongated structure and adistal end for separating the structure from the restricting tissue asthe elongated structure is received into the passageway. Also includedis a second tube having a passageway for receiving the elongatedstructure and the first tube for separating the restricting tissue fromeither the first tube or the elongated structure. Advantageously, atleast one of the two tubes comprises a polypropylene material, which ismuch less susceptible to kinking than teflon. In operation, two tubesare alternately moved along the elongated structure to provide tissueseparation. The second tube advantageously adding strength to theremoval apparatus for separating the restricting tissue. A controlmechanism having a passageway for passing the proximal end of theelongated structure therethrough is also attached to the proximal end ofthe first tube for controlling movement of the first tube in either arotational or longitudinal direction about the elongated structure. Tofacilitate visualization of the separating apparatus in biologicaltissue such as a blood vessel, at least one of the two tubes includes aradio-opaque material such as bismuth.

[0031] The invention also includes apparatus for separating the distalend of an elongated structure such as a pacemaker lead from heart tissueaffixed thereto. In one illustrative embodiment, the separatingapparatus includes first and second concentric tubes each having apassageway for receiving the structure to the distal end thereof. Anelongated member such as stainless steel wire or suture material isextendable between the distal ends for cutting the distal end of thestructure from the tissue. When the tubes are positioned at the distalend of the coiled structure, the tubes are rotated in oppositedirections to wipe the wire or suture material across the distal ends ofthe tubes and structure, thereby cutting the distal end of the structurefrom the affixed tissue. At least one of the tubes also has a secondpassageway or channel for controlling the amount and the tension of theelongated means at the distal ends thereof.

[0032] In a second illustrative embodiment, the separating apparatusincludes a tube having a passageway for receiving the lead. The distalend of the tube is extendable to the distal end of the pacemaker lead.Included at the distal end of the tube is a plurality of slots forreceiving the tines of the pacemaker lead. When the tines have beenpositioned in one or more of the slots, the tube is rotated forseparating the tines and distal end of the lead from the encapsulatingtissue.

[0033] The invention is further directed to apparatus for expanding theproximal end of a severed coiled structure of a pacemaker lead.Advantageously, this expands the wire coil structure of a pacemaker leadto insert a sizing stylet or gauge to accurately determine the diameterof the wire coil of the pacemaker lead. When the connector end issevered from the proximal end of the pacemaker lead, the severingoperation deforms the wire coil and provides a false indication of thetrue diameter of the passageway extending to the distal end of the lead.The expanding apparatus includes a tapered rod having distal end with afirst diameter that is easily insertable into a passageway of the coiledstructure of the pacemaker lead. The rod has a tapered longitudinalportion extending from the distal end to a proximal end having a seconddiameter greater than the first diameter. The tapered portion engagesand expands the proximal end of the severed coiled structure wheninserted therein. The apparatus also includes a control mechanismattached to the rod for controlling movement of the rod in thepassageway of the coiled structure.

[0034] The invention includes apparatus for removing an elongated coiledstructure implanted in biological tissue such as the wire coil of apacemaker lead implanted in the heart through a blood vessel leadingthereto. The apparatus includes a stylet wire that is insertable into alongitudinal passageway of the coiled structure for controlling movementof the structure. A wire coil is attached at its distal end to thedistal end of the stylet wire and is expandable for securing the styletwire to the coiled structure. The proximal end of the wire coil isextended from the wire coil and stylet wire for engaging the coiledstructure and for controlling expansion of the wire coil.

[0035] In another illustrative embodiment of this removal apparatus,first and second coil means, such as a wire coil having respective firstand second pluralities of turns, are positioned about the distal end ofthe stylet wire. The first coil means is attached about the distal endof the stylet wire and is radially expandable about the stylet wire forsecuring the stylet wire to the implanted lead when the stylet wire isinserted in the longitudinal passageway of the implanted lead. Thesecond coil means extends proximally from the first coil means andlaterally from the stylet wire for advantageously engaging the implantedlead and radially expanding the first coil means about the stylet wire.The second plurality of wire turns is formed to have a predeterminedlength and width for advantageously engaging the coil structure of theimplanted lead. Furthermore, the second plurality of wire turns andstylet wire cooperatively have a cross-sectional dimension approximatingthat of the implanted lead passageway. The first coil means alsoincludes a third plurality of closely-spaced wire turns that extendsdistally from the first plurality and that is positioned around andattached to the stylet wire. The second and third pluralities of wireturns cooperate to radially expand the first plurality of wire turns. Anenhancement to this illustrative embodiment includes a flat and atapered portion of the stylet wire that is positioned between the firstand third pluralities of wire turns for unremovably engaging the coiledstructure of the implanted lead. The width of this flat portionapproximates the width of the implanted lead passageway. The taperedportion extends proximally from the flat portion for advantageouslyexpanding the first plurality of wire turns within the passageway of theimplanted lead. The tapered portion more quickly expands the firstplurality of wire turns to engage the coiled structure of the implantedlead and secure it thereto without retraction of the stylet wire fromthe electrode of the implanted lead. In addition, the distal end of thestylet wire is tapered for easy insertion into the implanted leadpassageway.

[0036] In another embodiment of the lead removal apparatus of thepresent invention, the lead removal apparatus preferably includes atube, and control means for moving the coiled structure of a cardiaclead when secured to the coiled structure. The control means is slidablyarranged in the tube and has a distal end that is configured forinsertion into the passageway of the coiled structure. The expandablemeans is other than and separate from the control tube and is positionedproximate the distal end of the control means. The expandable means hasan expanded position in the passageway of the coiled structure forsecuring the control means to the coiled structure such that there is amore secure lock or engagement with the coiled structure and there areadvantageously fewer failures in the locking engagement, therebyproviding a more reliable mechanical connection. This particulararrangement also further provides greater size tolerance when selectingan appropriate lead removal apparatus and advantageously provides awider range of lead passageway sizes for a given stylet diameter. Thisconfiguration also provides for less dependence on physician techniqueand experience than the previously described coiled structure.

[0037] The expandable means of the lead removal apparatus advantageouslyincludes a laterally flexible member that extends longitudinally andproximally from the distal end of the control means. The laterallyflexible member advantageously thus has a proximal end for assuming anexpanded position and engaging the turns of a coiled structure. Thelaterally flexible member is attached to the distal end of the controlmeans and is further secured thereto with a sleeve positioned around thelaterally flexible member and control means. In one embodiment, thecontrol means comprises a stylet with the laterally flexible memberincluding a folded-back portion or a plurality of folded-back portionsof the stylet.

[0038] To facilitate fixing the relative positions of the stylet andouter tube, a lock is positioned at the proximal ends of the tube andstylet. For operation of the lead removal apparatus, handles arepositioned proximate the proximal ends of the control tube and stylet.

[0039] In another aspect of the invention, the lead removal apparatusthat includes a locking stylet and a radially expandable portion thatcomprises a plurality of expandable members. A actuator portion, such asa elongate cannula or section or coiled wire, is advanced against theexpandable portion, causing the latter to expand radially and engage thecoils of the pacemaker lead into which it has been introduced. In oneembodiment, the expandable portion comprises a wrap of multifilar wires(six to a bundle) that is helically wound around the distal portion of astylet pull wire. The multifilar bundle is soldered together and also tothe distal end of the stylet such that the expandable portion islongitudinally compressible. When compressed, the expandable members bowoutward and form an irregular-shaped, tangled mass that presses outwardagainst, and between the coils to provide positive engagement forsubsequent retraction of the pacemaker lead. To prevent prematureadvancement of the actuator portion and expansion of the expandablemember, an optional deployment guard, such as a severable ligature, cansecure the actuator portion and stylet together, generally via theirrespective handles.

[0040] In another embodiment of the invention, the expandable portioncomprises a series of longitudinally parallel wires that expand outwardwhen deployed. In still another embodiment, the expandable portioncomprises a slotted cannula in which the expandable members between thelongitudinal slots bow outward to engage the coils of the pacemakerlead.

[0041] The foregoing problems are solved and a technical advance isachieved in a lead apparatus, wherein the handle of the lead removalapparatus includes a proximal portion of the handle of a lead removalapparatus which is formed into a pre-shaped first configuration, such asa series of coiled loops. The coiled loops provide the operator with agreater ability to apply traction on the locking stylet and pacemakerlead and helping to maintain the proximal portion of the apparatuswithin the sterile field. The proximal portion can constrained into asecond, sufficiently straight configuration that allows the operator tofeed a medical device, such as a dilator sheath thereover, such as fordisrupting scar tissue encasing the lead along the path of the vein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0042]FIG. 1 depicts a partial cross-sectional view of a heart having anelectrical pacemaker lead implanted therein;

[0043]FIG. 2 depicts a partial cross-sectional view of a prior art toolinserted in the passageway of a heart lead for removing the lead;

[0044]FIG. 3 illustrates sections of the apparatus of the presentinvention for separating a length of a heart lead restricted in a bloodvessel and for separating the tip of the heart lead from a heart cavitywall;

[0045]FIG. 4 illustrates the leading edge of the separator tube of theapparatus of FIG. 3 for separating the heart lead from a blood vessel aspartially shown in FIG. 1;

[0046]FIG. 5 depicts a lockable mechanism for grasping the proximal endof the pacemaker lead of FIG. 1;

[0047]FIG. 6 depicts an enlarged view of the lockable mechanism of FIG.5 along the lines 6-6;

[0048]FIG. 7 depicts another embodiment of the lead removal apparatus ofthis invention;

[0049]FIG. 8 depicts the lead removal apparatus of FIG. 7 with thestylet wire secured to the pacemaker lead;

[0050]FIG. 9 depicts a device for expanding the proximal end of thecoiled structure of FIG. 3;

[0051] FIGS. 10-21 depict alternative embodiments of the removalapparatus of FIG. 3;

[0052]FIGS. 22 and 27 depict alternative embodiments of the apparatusfor separating encapsulating tissue from a pacemaker lead of FIG. 3;

[0053]FIG. 23 depicts an alternative embodiment of the apparatus forremoving an elongated coiled structure implanted in biological tissue ofFIG. 3;

[0054] FIGS. 24-26 depict illustrative apparatus for separating thedistal end of an elongated structure from tissue affixed thereto;

[0055]FIG. 28 depicts an alternative embodiment of the apparatus forremoving an elongated coiled structure implanted in biological tissue;and

[0056] FIGS. 29-31 depict an enhancement to the alternative embodimentof the apparatus for removing an elongated coiled structure implanted inbiological tissue of FIG. 28.

[0057]FIGS. 32 and 33 depict an alternative embodiment of the leadremoval apparatus of the present invention;

[0058]FIG. 34 depicts an enlarged, partially sectioned view of a portionof the expandable means or unit of the lead removal apparatus of FIG.33;

[0059]FIG. 35 depicts an alternative embodiment of an enlarged,cross-sectional view of the sleeve and stylet of FIG. 32;

[0060]FIG. 36 depicts an enlarged, cross-sectional view of theexpandable unit of the lead removal apparatus of FIG. 32 taken along theline 36-36;

[0061]FIG. 37 depicts an alternative embodiment of the expandable unitof the lead removal apparatus of FIG. 32;

[0062]FIG. 38 depicts an enlarged, cross-sectional view of theexpandable unit of FIG. 37 taken along the line 38-38; and

[0063]FIG. 39 depicts a partially sectioned side view of the controltube and stylet of the lead removal apparatus of FIG. 33.

[0064]FIG. 40 depicts a partially sectioned side view of an alternativeembodiment of the present invention having a multifilar, helicalexpandable portion;

[0065]FIG. 41 depicts a method of forming the expandable portion of theembodiment of FIG. 40;

[0066]FIG. 42 depicts a side view of an embodiment of the presentinvention having a expandable portion with longitudinally parallelelements;

[0067]FIG. 42A depicts a cross-sectional view taken along line 42A-42Aof FIG. 42;

[0068]FIG. 43 depicts a side view of an embodiment of the presentinvention wherein the expandable portion comprises a slotted cannula;

[0069]FIG. 43A depicts a cross-sectional view taken along line 43A-43Aof FIG. 43;

[0070] FIGS. 44-45 depicts a sectioned view of the embodiment of FIG. 40being deployed inside the coil of a pacemaker lead;

[0071]FIG. 46 depicts a side view of an embodiment of present inventionin which the proximal portion of the handle includes a compacted shape;and

[0072]FIG. 47 depicts a side view of a side view of an embodiment of thepresent invention in which the expandable portion and actuator portionform an unitary structure.

DETAILED DESCRIPTION

[0073] Depicted in FIG. 1 is a partial cross-sectional view of heart 215connected to a plurality of arteries and veins such as the rightsubclavian vein 216 through which an electrical heart pacemaker lead 204has been implanted. The lead passes internally through the rightsubclavian vein 216, the superior vena cava 208 and into the rightventricle 217 of the heart. The distal end of the lead includes anelectrode 220 for electrically stimulating the heart and is secured tothe apex of the right ventricle with a plurality of tines 207, which intime become securely attached to the ventricle wall by endothelialtissue forming around the heart lead tip. Some ventricles are relativelysmooth on the inside, but most have trabeculae amongst which the tinesare secured into position. External to the right subclavian vein, theproximal end 221 of the lead is grasped by a lockable mechanism 222,which will be described hereinafter.

[0074] Depicted in FIG. 2 is a partial cross-sectional view of a priorart tool 100 for removing a heart lead 111 which has been secured to aheart cavity wall 113 via trabeculae and/or fibrotic tissue 104. Thelead includes an electrical coiled structure 101 and insulating material102 that is formed essentially into a tube for covering the outersurface of the coiled structure and for preventing fluids from enteringthe coiled structure. At the distal end of the heart lead are tines 103,that are formed from the insulating material, for securing the heartlead tip including electrode 109 to the heart cavity wall. Tool 100includes a hollow rigid tube 105 and beveled rod 106 for inserting inthe longitudinal passageway 110 of the heart lead coiled structure. Inthe passageway of hollow tube 105 is an actuating wire 107 connected tobeveled rod 106. The trailing edge of the beveled rod and the leadingedge of the hollow tube are inclined at an angle for moving the beveledrod across the distal end of the hollow tube when the actuating wire ispulled. When moved, the beveled rod engages and deforms the heart leadcoiled structure as shown. The deformed coiled structure locks thehollow tube and beveled rod in place for limiting movement of the heartlead. However, once secured, beveled rod 106 may not be extracted frompassageway 110 of the coiled structure since the deformed coiledstructure prevents the beveled rod and actuating wire from traversingthe passageway. The prior art tool also includes a hollow dilator 108for sliding over the heart lead coil and separating the heart lead fromthe blood vessel. A hollow explanator 112 passes over the dilator and isrotated back and forth to explant the tip of the heart lead from thesecuring tissue and heart wall.

[0075] Depicted in FIG. 3 is a flexible stylet wire 200 of the presentlead removal apparatus invention that is insertable in the longitudinalpassageway 210 of a heart lead coiled structure 211 for controlling and,in particular, limiting the movement of heart lead 204 including coiledstructure 211. Heart lead 204 also includes insulating material 201,such as silicone or polyurethane, formed into a hollow tube thatsurrounds the coiled structure and prevents fluids from making contactwith the coiled structure. Attached to the distal end of the flexiblestylet wire is an expandable wire coil 205 consisting of approximately25 turns of wire with spacing between the turns. Five to seven wraps ofthe wire coil are attached to the distal end of the stylet wire using,for example, solder 206. The remaining wraps of the wire coil remainfree for engaging the coiled structure when the proximal end of thestylet wire is rotated in a direction to unwind and expand the turns ofthe wire coil and engage the coiled structure of the heart lead. A bead214 of high temperature silver solder is applied to the distal end ofthe stylet wire to prevent the distal end thereof from pulling throughthe wire coil during separation and removal of the heart lead.Positioned about the proximal end of the stylet wire is controlmechanism 202 for rotating the stylet wire in either a clockwise orcounterclockwise direction or for moving the wire in a longitudinaldirection into or out of the passageway. In this embodiment, controlmechanism 202 is a loop of wire formed from the stylet wire of which thephysician may grasp or insert his finger. The loop may also be fashionedfor attachment to another control mechanism for moving the stylet wire.Other control mechanisms such as a slidable chuck may be positioned atthe proximal end of the stylet wire to facilitate movement of the styletwire. The formed loop 202 is covered with teflon tubing 203 or othersuitable material for facilitating the easy movement of the stylet wire.The looped end is also compressible for inserting through a separatortube 212.

[0076] The choice of the stylet wire and wire coil varies with theinternal diameter of the coiled structure which varies from 0.016″ toabout 0.028″ for most heart leads. The diameter of the stylet wire wouldthen range from 0.009″ to 0.015″, with the coil wire ranging in diameterfrom 0.003″ to 0.006″. The use of stainless steel wire is preferable.The stylet wire should be hardened wire, but ductable wire may be usedfor the coil wire.

[0077] Before the stylet wire is inserted into passageway 210 of thelead, the inside diameter of the coiled structure and the outsidediameter of the insulating material are determined. First, lockablemechanism 222 is first applied to the proximal end 221 of the leadbetween opposing semicircular jaws 223 and 224. The details of mechanism222 are depicted in FIGS. 5 and 6. Semicylindrical pliable material 225and 226, such as latex, are affixed with medical grade adhesive to theopposing faces of the jaws. Semicylindrical pliable material 225includes semicylindrical channels 227 and 229 having different radii,and pliable material 226 includes semicylindrical channels 228 and 230with radii corresponding to channels 227 and 229, respectively. Whenjaws 223 and 224 are in a closed position, the opposing surfaces 231 and232 of respective pliable material 225 and 226 are in contact withopposing channels 227 and 228 forming one hollow cylindrical passagewaywith a first diameter and opposing channels 229 and 230 forming a secondhollow cylindrical passageway with a second larger diameter. The twodifferent size diameter passageways in the pliable material accommodatea number of different size diameter pacemaker leads and are designed tograsp and apply pressure to insulating material 201 in a uniform manner.

[0078] When proximal end 221 of lead 204 is inserted and grasped in thehollow passageway formed by channels 229 and 230, insulating material201 is compressed onto coiled structure 211, thus limiting the movementof the structure within the insulating material. When the physician cutsthe lead for access to the passageway of the lead, the compressedinsulating material prevents the coiled structure from retracting intothe passageway of the lead.

[0079] Pivotally interconnected elongated members 233 and 234 areconnected to respective opposing jaws 223 and 224 to operate the jawsbetween open and closed positions. The proximal ends 235 and 236 of themembers are curved as shown in FIG. 5 to oppose each other and have arespective plurality of teeth 237 and 238 that interlock to form alocking mechanism. The locking mechanism is actuated by squeezing theproximal ends of the members and opposingly positioning the teeththereon. When so positioned, the teeth of mechanism 222 interlock andmaintain opposing jaws 223 and 224 in a closed position.

[0080] After the lockable mechanism is applied to the proximal end ofthe pacemaker lead, a pair of well-known wire cutters or snips sever theelectrical connector (not shown) from the proximal end 222 of pacemakerlead 204. As a result of such severance, coiled structure 211 of thepacemaker lead is commonly deformed, thereby presenting a falseindication of the actual diameter of longitudinal passageway 210. As aconsequence, the physician inserts expansion device 901 into theproximal end of hollow passageway 210 to expand coiled structure 211.

[0081] Depicted in FIG. 9 is expansion device 901 for expanding thedeformed proximal end of coiled structure 211. The expansion deviceincludes a tapered rod 902 having a distal end 903 with a diameter thatis easily insertable into the passageway of the deformed coiledstructure. Tapered rod 902 includes a tapered longitudinal portion 904that gradually increases in diameter to proximal end 905 that has adiameter significantly greater than the diameter of the distal end.Control handle 906 is connected to the proximal end of the tapered rod.The physician grasps the control handle to insert the tapered rod intothe longitudinal passageway and to expand the deformed proximal end ofthe coiled structure.

[0082] With lockable mechanism 222 in a closed position and the proximalend of the coiled structure expanded, the physician selects a wire guide239, as shown in FIG. 3, having a diameter less the diameter of the leadpassageway. The physician determines the passageway by inserting thewire guide therein and sensing for any blockages. The guide includes acontrol mechanism such as a knurled cylindrical chuck 240 positionableabout the proximal end thereof. The physician grasps the knob to extendthe guide into the lead passageway and to rotate the guide back andforth to clear or break through any blockages caused by tissue oroccluding material. The guide is also used to determine or size theinside diameter of a second coiled structure that may be coaxiallypositioned inside coiled structure 211. When utilized as a controlmechanism for stylet wire 200, the chuck may also include appendages 260for rotating and counting the number of times the stylet wire isrotated. Having determined the lead passageway with the wire guide,several other guides similar to guide 239 are individually inserted inthe passageway to determine the actual inside diameter at the proximalend. Guide 239 is also utilized to determine if coiled structure 211 hasbeen deformed or damaged and to determine the smallest diameter of thecoiled structure and passageway.

[0083] As shown in FIG. 3, stylet wire 200 is inserted into longitudinalpassageway 210 of coiled structure 211. The diameter of the coil wireand stylet wire have been selected to form a combined overall diameterwhich approximates the diameter of the longitudinal passageway of theheart lead coiled structure within a predetermined tolerance such as oneor two thousandths of an inch. Stylet wire 200 is then fed through theentire length of the passageway to the distal end of the coiledstructure which is secured to the wall of heart cavity tissue 213 viatines 207. When fully inserted into the heart lead, the distal ends ofthe stylet wire and coiled structure should be in close proximity. It isnot necessary, but probably more advantageous, that the stylet wire beattached to the distal end of the heart lead. For separating the heartlead from adjacent tissue, the stylet wire may be secured anywhere alongthe passageway of the coiled structure past the restricting tissue. Tosecure the stylet wire to coiled structure 211, looped end 202 of thestylet wire is operated in a circular direction to unwind and expandwire coil 205. As a result, the turns of the wire coil and coiledstructure engage and intermesh, thereby firmly securing the stylet wireto the heart lead. This prevents any extension or stretching of theheart lead and also controls and limits the movement of the lead whenseparator tube 212 is moved along the length of coiled structure 211 andinsulating material 201 of the heart lead.

[0084] Depicted in FIG. 23 is illustrative removal apparatus 2301, whichis an alternative embodiment of stylet wire 200. Removal apparatus 2301is insertable into the longitudinal passageway of an elongated structuresuch as a pacemaker lead. The removal apparatus includes a stylet wire2302 with a conically-shaped silver solder tip 2303 that is positionedat the distal end thereof. Closely wrapped wire coil 2304, similar towire coil 205, is attached at the distal end of the stylet wire usingsilver solder 2305 as previously described. The proximal end of the wirecoil is pulled to unwrap several turns of wire coil 2304. A pigtail 2306is formed from the proximal end of the wire coil to extend in a radialdirection from the wire coil and stylet wire. Pigtail 2306 catches on orengages the coiled structure of the pacemaker lead to engage wire coil2304 with the coiled structure of the pacemaker lead. In addition, thewire coil may be rotated in the opposite direction to release the styletwire from the coiled structure if desired.

[0085] Depicted in FIG. 28 is illustrative removal apparatus 2801, whichis an alternative embodiment of stylet wire 200. Removal apparatus 2801is insertable into the longitudinal passageway of an elongated structuresuch as a pacemaker lead. The removal apparatus includes stylet wire2802 comprising commercially available stainless steel wireapproximately 0.021″ in diameter and 61 cm in length. Stylet wire 2801has distal end 2803 which is tapered into a conical shape for anapproximate length of 4 cm for easy insertion into the pacemaker leadpassageway. Tapered distal end 2803 is shaped using any of a number ofwell-known techniques such as sanding, grinding, buffing, or acombination thereof. The removal apparatus also includes wire coil 2804comprising commercially available Tophel wire approximately 0.0045″ indiameter. Wire coil 2804 is positioned around and about stylet wire 2802and comprises central plurality of wire turns 2805. Central plurality2805 extends longitudinally from approximately 20 cm and comprises wireturns with a spacing of approximately 0.035″ therebetween. Wire coil2804 further comprises a proximal plurality of wire turns 2806, whichextends proximally from the central plurality and laterally from thestylet wire, and a distal plurality of wire turns 2807, which extendsdistally from the central plurality. Proximal plurality of wire turns2806 has a nominal outside diameter of 0.010″ and a maximum diameterwidth of 0.012″. The proximal plurality is formed from turns having an0.010″ inside diameter that are stretched to an outside diameter ofapproximately 0.010″, thus increasing the spacing between each turn. Thelength of the proximal plurality is trimmed to a length of approximately12 mm. When inserted in the lead passageway, the stylet wire andproximal plurality in combination have a cross-sectional dimension thatapproximates that of the passageway for engaging the coiled structure ofthe lead and radially expanding the central plurality of wire turns. Thedistal plurality comprises approximately five turns with minimal spacingtherebetween, much less than that of central plurality 2805. The distalplurality of wire turns is wrapped about the distal end of the styletwire next to silver solder bead 2808 and attached thereto withtin-silver solder 2809. The silver solder bead and distal plurality ofwire turns are tapered into a conical shape having a maximum outsidediameter of, for example, 0.030″ for easy insertion in the passageway ofthe lead.

[0086] When apparatus 2801 is positioned in the passageway of animplanted pacemaker lead, in particular a lead having a 0.030″ diameterpassageway, the proximal plurality of wire turns creates an interferencefit in the passageway. During insertion to distal end of the pacemakerlead, the apparatus is alternately pushed distally and pulled proximallya short distance for maintaining the interference fit effected by theengagement of the proximal plurality with the coiled structure of thepacemaker lead. When the distal end of the stylet is positioned in thepassageway of the distal end of the pacemaker lead, stylet wire 2801 isrotated in a counter-clockwise direction for unwrapping several turns ofcentral plurality 2805. The unwrapped turns of the central pluralityfurther engage and secure the wire coil of the apparatus with the coiledstructure of the pacemaker lead.

[0087] Depicted in FIGS. 29 and 30 is illustrative removal apparatus2901, which represents an enhancement to apparatus 2801 of FIG. 28.Removal apparatus 2901 includes stylet wire 2902 of commerciallyavailable 0.021″ diameter stainless steel wire having tapered portion2903, flat portion 2904, and distal end 2905. Removal apparatus 2901further includes wire coil 2906 having a central plurality of wire turns2907, a distal plurality of wire turns 2908, and a proximal plurality ofwire turns 2910. Wire coil 2906 also includes a somewhat straightportion 2909 extending longitudinally between the central and distalpluralities. Distal plurality 2908 is closely spaced, much less than thecentral plurality, and fixedly attached with tin-silver solder 2911about the distal end of the stylet wire next to silver solder bead 2912.As shown in the top view of FIG. 30, tapered portion 2903 and flatportion 2904 of the stylet wire is positioned between the distal andcentral pluralities of wire turns and has a maximum width of 0.030″ thatapproximates the width of the passageway of the implanted lead. Straightportion 2909 of the wire coil extends longitudinally from the centralplurality along stylet wire 2902 where the diameter of the stylet wireis uniform. Straight portion 2909 further extends longitudinally alongtapered portion 2903, which has a 30 degree tapered edge, and flatportion 2904, which has an edge parallel the stylet wire. Taperedportion 2903 and flat portion 2904 are each approximately 0.15″ long.

[0088] As depicted in FIG. 31, removal apparatus 2901 is positioned inpassageway 3001 and secured to coiled structure 3002 of implantedpacemaker lead 3003. Stylet wire 2902 has been rotated in acounter-clockwise direction to wrap straight coil portion 2909 aroundtapered stylet portion 2903. The wrapped straight coil portion engagesthe coiled structure of the lead and secures the stylet wire to theimplanted lead. As the straight coil portion is wrapped around thetapered stylet portion, turns of the central plurality move distally toexpand and engage the tapered stylet portion and the coiled structure ofthe implanted lead.

[0089] Depicted in FIGS. 10-21 are alternative embodiments ofillustrative apparatus for removing the elongated structure implanted inbiological tissue. All of these alternative embodiments are forcontrolling the movement of an elongated structure. The removalapparatus in each of these alternative embodiments includes a controlunit that is insertable into the longitudinal passageway of theelongated structure, such as a pacemaker lead, and securable to thestructure for controlling the movement thereof. The apparatus alsoincludes an expandable unit positioned about the distal end of thecontrol unit and operable to an expanded position for securing thecontrol unit to the elongated structure. However, the control unit ineach of these alternative embodiments commonly, but not in all cases,includes a longitudinal passageway for operating the expandable unit tothe expanded position for securing the control unit to the elongatedstructure.

[0090] Depicted in FIG. 10 is a first alternative embodiment ofillustrative removal apparatus 1001 for removing implanted pacemakerlead 204. The control unit of this removal apparatus includes a flexibletube 1002 having a passageway 1003 formed longitudinally therein.Expandable balloon 1004 is positioned and attached about the distal endof the control tube. The distal end of the control tube is also recessedto attach to the balloon in a well-known manner at the ends of radialrecess 1005. The recess also provides a volume in which the collapsedballoon is stored. The recess also includes one or more side ports 1006leading from passageway 1003 to the balloon. A source of fluid such ascompressed air or liquid is passed through the passageway and into theballoon to inflate the balloon to an expanded position as indicated byexpanded balloon 1007 positioned at the distal end of the lead.

[0091] Depicted in FIG. 11 is a second alternative embodiment ofillustrative removal apparatus 1100. In this second alternativeembodiment, the control unit also includes a control tube 1101 forinsertion into passageway 210 of coiled structure 211. The expandableunit comprises a plurality of radial projections 1102 and 1103 that havea free end are radially formed in the distal end of the control tube.The free end of the radial projection is twisted and bent in an inwarddirection into passageway 1104 of the control tube. As formed, theseprojections allow a control tube to be easily inserted into passageway210 of the coiled structure. When control tube 1101 is positioned at thedistal end of the coiled structure, actuator rod 1105 is inserted inpassageway 1104 of the control tube. When inserted, the actuator rodengages the radial projections and forces them into an expanded positionextending radially from the surface of the control tube into the coiledstructure of the pacemaker lead. When in the expanded position, theseradial projections secure the control tube to the coiled structure,thereby controlling movement of the coiled structure during removal fromthe tissue.

[0092] Depicted in FIG. 12 is a third alternative embodiment ofillustrative removal apparatus 1201 utilizing an actuator rod 1202. Theremoval apparatus includes a control tube 1203 that is extendable intothe longitudinal passageway of a pacemaker lead. The expandable unit ofthe apparatus comprises a plurality of longitudinal strips 1204 formedat the distal end of the control tube. Actuator rod 1202 is inserted inthe passageway of the control tube and attached to the distal end 1205thereof. When the control tube is inserted in the longitudinalpassageway of the pacemaker lead, the actuator rod 1202 is pulled in alongitudinal direction out of passageway 1206 of the control tube asshown by arrow 1207. Typically, the physician will maintain the relativeposition of the proximal end of control tube 1203 while the actuator rodis pulled in the outward direction. As a result, distal end 1205 isforced toward the proximal end of the control tube, as shown by arrow1208, thereby deforming longitudinal strips 1204 in an outward directionas indicated by arrows 1209. The expanding strips engage the coiledstructure and secure the control tube to the coiled structure of thepacemaker lead.

[0093] Depicted in FIG. 13 is a fourth embodiment of illustrativeremoval apparatus 1301 inserted in the longitudinal passageway 210 ofcoiled structure 211. Removal apparatus 1301 includes a control tube1302 having a distal end with a spiral or helical ridge 1303 formedtherein. Alternatively, a number of barbs are formed in the contoureddistal end of control tube 1302. The distal end includes a plurality ofslits 1307 or an opening thereat for expanding the ridge or barbs intothe coiled structure. Actuator rod 1304 is inserted into passageway 1305to engage the distal end. When engaged, actuator rod expands the ridgeor barbs in a radial direction, as shown by arrows 1308, to engage thecoiled structure of the pacemaker lead. As a result, the expanded ridgeor barbs secure the control tube to the coiled structure for controllingthe movement thereof.

[0094] Depicted in FIG. 14 is a fifth embodiment of illustrative removalapparatus 1401 inserted in longitudinal passageway 210 of coiledstructure 211. The removal apparatus includes control tube 1402 andactuator rod 1403 extending through hollow passageway 1404 of thecontrol tube. The apparatus also includes a diagonally-slotted sleeve1405 that is positioned between the distal ends of the control tube andactuator rod. The actuator rod also extends through hollow passageway1406 of the sleeve. Attached to the distal end of the actuator rod isbeveled tip 1407 having an outside diameter approximating the diameterof the control tube and the nominal diameter of the slotted sleeve.Similarly, the distal end of the control tube is beveled to engage andexpand the slotted sleeve. To expand the slotted sleeve, the actuatorrod is pulled, as indicated by arrow 1408, to engage the sleeve againstthe beveled edges of the control tube and the rod. As a result, thesleeve is expanded to a position for engaging coiled structure 211 andsecuring the control tube thereto. The slotted sleeve expands in aradial direction as indicated by arrows 1409.

[0095] Sixth and seventh alternative embodiments of illustrative removalapparatus 1501 and 1601 are depicted in FIGS. 15 and 16, respectively.In FIG. 15, removal apparatus 1501 includes a control tube 1502 and anactuator rod 1503 extending through longitudinal passageway 1504 of thecontrol tube. The distal end of the actuator rod includes enlarged tip1505 having a diameter approximating the diameter of the control tube.The device also includes expandable sleeve 1506 comprising a pliablematerial such as synthetic rubber and the like which expands in a radialdirection when compressed between the distal end of the control tube andthe enlarged tip of the actuator rod. In the relaxed state, the outsidediameter of the pliable material approximates that of the control tubeand enlarged tip of the actuator rod for insertion into longitudinalpassageway 210 of the coiled structure. When inserted into passageway210, the enlarged tip and distal end of the control tube compress andradially expand the pliable material in an outward direction toward thecoiled structure as indicated by arrows 1507. The actuator rod is pulledthrough the passageway of the control tube as indicated by arrow 1508.As a result, pliable material 1506 is longitudinally compressed as shownby arrows 1509 and 1510. However, pliable material 1506 also expands ina radial direction and engages the coiled structure, thereby securingthe control tube thereto.

[0096] Similarly, illustrative removal apparatus 1601 depicted in FIG.16 includes control tube 1602 having longitudinal passageway 1610,actuator rod 1603 having an enlarged distal tip 1604, and pliablematerial 1605 attached to the distal end of control tube 1602 andenlarged actuator rod tip 1604. However, unlike pliable material 1506,pliable material 1605 in a relaxed condition has an outside diametergreater than the diameter of longitudinal passageway 210. Therefore, toinsert the removal apparatus in the passageway, actuator rod is forcedinto passageway 1610 as indicated by arrow 1606, thereby stretchingpliable material 1605 as indicated by arrows 1607 and 1608. As a result,the outside diameter of the pliable material decreases as indicated byarrows 1609 for insertion into the passageway of the elongatedstructure. When inserted, the actuator rod is released, and the pliablematerial attempts to return to its relaxed state. As a result, thepliable material engages the coiled structure and secures the device tothe pacemaker lead.

[0097] Depicted in FIGS. 17 and 18 are alternative embodiments ofillustrative removal devices 1701 and 1801 that include a wire guide forinserting into the longitudinal passageway of the elongated structure.In FIG. 17, removal apparatus 1701 includes wire guide 1702 that isinserted into passageway 210 of coiled structure 211 to clear anyblockage formed therein and establish a guide for control tube 1703.When the guide wire is fully inserted, the control tube is inserted overthe guide wire and then into passageway 210 of the structure. Thecontrol tube also has a longitudinal passageway 1706 for receiving thewire guide therein. Also included is wire coil 1704 that is positionedand attached at the distal ends thereof using, for example, silversolder 1705. As previously described with respect to stylet wire 200,control tube 1703 is rotated in a direction opposite that of coiledstructure 211 for engaging and expanding wire coil 1704, therebysecuring the control tube to the coiled structure.

[0098] As depicted in FIG. 18, removal apparatus 1801 includes wireguide 1802 that is inserted into the passageway of the elongatedstructure. Control tube 1803 includes two longitudinal passageways 1804and 1805. Passageway 1804 receives the wire guide as the control tube isinserted into the passageway of the elongated structure. Positioned atthe distal end of the control tube is inflatable balloon 806 withpassageway 1805 leading thereto through sideport or aperture 1807. Tosecure the control tube to the elongated structure, a fluid is passedthrough passageway 1805 to inflate the balloon to an expanded position.

[0099] Several other alternative embodiments of illustrative removalapparatus are depicted in FIGS. 19-21. Depicted in FIG. 19 is removalapparatus 1901 that includes control tube 1902 and cylinder 1903. Thetube includes longitudinal passageway 1904. Cylinder 1903 is positionedabout the distal end of the control tube and rotated to a positionoff-center of the tube for securing the control tube to the elongatedstructure. The removal apparatus includes an actuator rod 1904 extendingthrough the control tube and attached to the rotatable cylinder. The rodrotates the cylinder to an off-centered position for securing thecontrol tube to the elongated structure such as the coiled structure ofa pacemaker lead. Actuator rod 1904 extends between the rotatablecylinder and control mechanism 1905 that is positioned at the proximalend of the control tube. Control mechanism 1905 is rotatable between twopositions for rotating the actuator rod and the cylinder betweenexpanded and retracted positions. The actuator rod is attached to thecylinder at an off-centered position to permit rotation of the cylinderand engagement of the elongated structure. Plug 1907 is inserted at thedistal end of the tube to maintain the off-centered position of the rodin the passageway.

[0100] Depicted in FIG. 20 is illustrative removal apparatus 2001including a control tube 2002 that has a longitudinal projection 2003extending at the distal end thereof for securing the control tube to thecoiled structure of a pacemaker lead. This arrangement is sometimesreferred to as a flea-clip arrangement. Depicted in FIG. 21 is asectioned view, taken along the lines 21-21 in FIG. 20, of the apparatusin passageway 210 of coiled structure 211. As shown, a stylet wire orrod 2004 is inserted into passageway 2005 of control tube 2002 to engageand retract the extended projections into the wall of the control tube.When the apparatus is inserted to the distal end of the coiledstructure, the stylet wire or rod is removed from the passageway of thecontrol tube. As a result, the spring-like projections extend into thecoiled structure of the lead, thereby securing the control tube to thecoiled structure for controlling the movement thereof. To remove thecontrol tube, the rod is inserted into the control tube passageway asshown by arrow 2101 to again engage the projections. When the rodengages the projections extending into the passageway, the inwardextending projections move into the wall in a direction as shown byarrows 2103, whereas the outward extending projections move into thewall in a direction as shown by arrows 2102.

[0101] The reader's attention is again referred to the preferredembodiment depicted in FIG. 3. After the stylet wire is secured to thelead and prior to inserting separator tube 212 over the stylet wire andlead, a tie 241 of, for example, nylon cord or suture material iswrapped around proximal end 221 of the lead to secure insulatingmaterial 201 to coiled structure 211. The tie controls or limits themovement of the coiled structure within the insulating material. Withthe insulating material secured to the coiled structure at the proximalend, removal force is applied not only to the coiled structure, but alsoto the insulating material of the lead as well. This maintains theintegrity of the heart lead during subsequent tissue separation from theinsulating material. In those instances where the stylet wire has notbeen fully inserted to the distal end of the lead, the tie also preventsthe coiled structure from unraveling, breaking or separating fromelectrode 220 or the rest of the lead.

[0102] As previously suggested, the looped proximal end of the styletwire can be compressed to permit separator tube 212 to be insertedthereover and over the insulating material of the heart lead. Separatortube 212 comprises a semi-rigid material, such as teflon, for slidingeasily through the blood vessel and over the insulating material of theheart lead. In order to place the separator tube over the stylet, thestylet should extend at least 12 inches beyond the person's body so thatthe looped end can be grasped to apply tension to the stylet. With theteflon separator tube 10 to 12 inches long, the stylet is typicallythree feet long.

[0103] Depicted in FIG. 4 is fibrotic tissue 209 encapsulating heartlead 204 in blood vessel 216. When this occurs in small diameter veinswhere blood flow has been restricted or prevented, separation andremoval of the lead from the tissue is difficult and often causes severedamage or destruction to the vein. Without tension on stylet wire 200,separation is usually not possible in these situations.

[0104] As shown, the distal end of the Teflon separator tube 212 isbeveled and includes a cutting edge or edge having a number of teeth forseparating heart lead insulating material 201 from encapsulatingfibrotic tissue 209. As depicted in FIG. 7, hollow separator tube 212has a metal beveled tip 242 attached to the distal end thereof with, forexample, a medical grade adhesive. The metal tip provides a more durableedge for separating or cutting encapsulating fibrotic tissue from thelead.

[0105] Returning the reader's attention again to FIG. 3, separator tube212 is moved and rotated along the outer surface of insulating material201 of the heart lead to separate the lead from the blood vessel wall.After the separator tube has been moved along the entire length of theheart lead, it will abut next to the heart cavity wall as shown byphantom lines 219. The distal end of the heart lead is typically securedto the heart cavity wall by trabeculae or fibrotic tissue 218 that hasencapsulated tines 207 positioned at the distal end of the lead. Theseparator tube 212 is positioned next to the heart cavity wall or pushedslightly while the stylet wire is tensioned in the opposite direction.The separator tube is then rotated back and forth to dislodge andseparate tines 207 and the distal end of the heart lead from fibrotictissue 218 and heart cavity wall 213. As a result, the heart lead hasnow been completely separated from the blood vessel and the heart cavitywall for subsequent removal. The separator tube, the stylet wire, andthe heart lead are then removed from the heart cavity and surroundingblood vessel.

[0106] However, should the removal of the heart lead be prevented forwhatever reason, the stylet wire is rotated in a clockwise direction tounsecure the stylet and wire coil from the heart lead coiled structure.The time for this operation is lessened by attaching a rotatingmechanism such as an electrical screwdriver to the proximal end of thestylet wire.

[0107] Depicted in FIG. 27 is an alternative embodiment of illustrativeseparator apparatus 2700. This separator apparatus includes a set ofseparator and dilator tubes 2701 and 2702 for insertion over pacemakerlead 204. Similar to separator tube 212, separator tube 2701 has ahollow passageway therein for receiving the pacemaker lead. Theseparator tube is advanced along the lead to engage and separateencapsulating tissue from the lead. Dilator tube 2702 similarly has ahollow passageway therein for receiving separator tube 2701 and thepacemaker lead therein. A preferred material for separator and dilatortubes 2701 and 2702 is polypropylene which is more kink-resistant thanTeflon. A polypropylene tube fits easily into the blood vessel forextension to the distal end of the pacemaker lead. Furthermore, theinclusion of approximately 25% of bismuth provides radio-opacity forviewing with, for example, a fluoroscope during insertion of theseparator tube. When the dilator tube is inserted over the separatortube and lead, a control mechanism 2703 having a hollow passagewaytherein is inserted over the lead and connected to the proximal end ofseparator tube 2101. Control mechanism is well-known as a pinvise and isused for controlling the movement of the separator tube in both alongitudinal and rotational direction. The dilator tube and separatortube are alternatively moved along the lead to first separate the tissuefrom the lead and further dilate the tissue with the dilator tube. Thecontrol mechanism 2103 provides added strength and control during themovement of the separator tube. Dilator tube 2102 not only providesextra dilation of the tissue but also provides additional strength tothe entire structure for separating tissue from the pacemaker lead.

[0108] Depicted in FIG. 22 is another alternative embodiment ofillustrative separator apparatus 2201 for separating encapsulatingtissue 2205 from pacemaker lead 204. The separator apparatus 2201includes a tube 2202 having a longitudinal passageway 2203 therein forreceiving and passing over the pacemaker lead including outer insulatingmaterial 201. Distal end 2204 of the tube is beveled to provide a wedgefor separating encapsulating tissue 2205 from the pacemaker lead. Alsopositioned and attached in a well-known manner about the distal end ofthe separator tube is balloon 2206. The tube also includes a pluralityof hollow passageways 2207 for supplying a compressed gas or fluid forinflating the balloon. Separator apparatus is inserted over theinsulating material sheath of the pacemaker lead to engage encapsulatingtissue 2205. The beveled distal end provides a wedge for causing aninitial separation of the tissue from the lead. Upon initial contact andseparation, the balloon is inflated to provide further dilation andseparation of the encapsulating tissue from the pacemaker lead. Theballoon is then deflated to permit the beveled distal end to be furthermoved along the pacemaker lead and engage additional encapsulatingtissue. This process is continued until all of the encapsulating tissueis separated from the pacemaker lead.

[0109] Depicted in FIGS. 24 and 25 is separator apparatus 2401 forseparating the distal end of an elongated structure such as electrodetip 220 of pacemaker lead 204 from tissue 218 affixed thereto. Thisapparatus is particularly advantageous in those instances where theelectrode of the pacemaker lead is porous allowing fibrotic tissue togrow therein and secure the electrode tip thereto. Separator apparatusincludes a first tube 2402 having a hollow passageway 2403 for receivingpacemaker lead 204 and extending to the distal-end thereof. Attached tothe distal end of the first tube 2402 is an elongated member such asstainless steel wire 2404. The first tube wall also has a hollow channelor passageway 2408 extending longitudinally therethrough for passing thewire the entire length of the tube. Alternatively, the stainless steelwire can be affixed to the distal end using any suitable well-knownfastening means. A second tube 2405 also has a longitudinal passageway2406 for receiving the first tube. In addition, the second tubesimilarly includes a hollow channel or passageway 2407 for extendingstainless steel wire 2404 through the entire length of the tube andbeyond the proximal end thereof. This permits the loose end of the wireto be controlled by the clinician to remove the distal end of thepacemaker lead from the encapsulating or affixed tissue. As shown inFIG. 25, the first tube is extended to the distal end of the pacemakerlead and placed next to electrode 220. The second tube with thestainless steel wire is then also positioned next to the distal end ofthe pacemaker lead next to the electrode. The clinician puts tension onthe stainless steel cutting wire and then rotates the second tuberelative to the first causing the stainless steel wire to wipe acrossthe face of the electrode as shown. Rotation of the two tubes are shownby arrows 2501 and 2502. This wiping motion across the pacemakerelectrode literally cuts the electrode tip free from the encapsulatingor affixed tissue 218. Instead of stainless steel wire, suture materialis also used to perform the cutting action.

[0110] Depicted in FIG. 26 is a second alternative embodiment ofillustrative separator apparatus 2601 for separating the distal end of apacemaker lead having a plurality of tines such as tines 207 ofpacemaker lead 204 encapsulated in fibrotic heart tissue 218. Apparatus2601 includes tube 2602 having a longitudinal passageway 2605 forreceiving pacemaker lead 204. The tube is inserted over the lead andextended to the distal end thereof. The tube includes a plurality ofslots 2603 formed at the distal end for receiving pacemaker lead tines207. When the tines are received in the slots, tube 2602 is rotated backand forth in a circular motion for dislodging and separating the tinesfrom the encapsulating tissue 218 extending from heart wall tissue 213.

[0111] Depicted in FIG. 7 is another illustrative embodiment of the leadremoval apparatus of this invention. In this embodiment, pacemaker lead243 is similar to the lead shown in FIG. 3; however, the distal end ofthe lead is of a different configuration. In particular, electrode 244has two cavities therein. One cavity is for receiving the coiledstructure 245 of the lead. The second cavity is for receiving andsecuring anchoring coil 246 secured in the cavity with insulatingmaterial 247 in a well-known manner. The distal end of anchoring coil246 is cut to form a beveled or sharpened edge for turning orcorkscrewing the coil into heart cavity wall 213. Anchoring coil 246, asa result, securely attaches electrode 244 to the heart tissue toestablish good electrical contact for stimulating the heart tissue withelectrical pacing pulses from the pacemaker. Insulating material 248surrounds coiled structure 245 and partially surrounds electrode 244.Since anchoring coil 246 is utilized in this configuration, theinsulating material is molded over the coiled structure and electrodewithout forming tines for the endothelial tissue to form therearound.

[0112] Stylet wire 249 of this lead removal apparatus and lock wire 250attached to the distal end thereof have a combined diameter much lessthan the inside diameter of coil structure 245 of the lead. This isparticularly advantageous for those situations when the coiled structureof the lead has been deformed, unraveled, or in some way damaged. Inthis embodiment, lock wire 250 has a plurality of turns 251 wrappedaround the distal end of the stylet wire. Turns 251 of the lock wire atthe distal end of the stylet wire are closely wrapped and attached tothe distal end of the stylet wire using, for example, a silver solder.Turns 252 of the lock wire are more loosely wrapped and areapproximately 75 in number. The unwrapped proximal end 253 of the lockwire extends beyond the passageway of the lead and is secured andpositioned by, for example, the physician's hand 258 when the styletwire is rotated to expand lock wire turns 252 and engage the turns ofcoiled structure 245.

[0113] Control mechanism 254 such as a loop of malleable wire is wrappedaround and secured to the proximal end of the stylet wire using, forexample, silver solder 257. Slidable chuck 240 is also suitable for useas the control mechanism for stylet wire 249. A Teflon coating 255surrounds the interconnection to prevent possible injury to thephysician or patient. Control loop 254 is provided for the physician tomove the stylet wire in and out of the passageway of the lead as well asrotate the stylet wire to engage the coiled structure of the lead. Whenthe stylet wire is secured to the pacemaker lead, loop 254 is used toextract stylet wire and pacemaker lead from the patient.

[0114] To unravel the turns of the lock wire, a tool such as anelectrical screwdriver is attached to the control mechanism loop torotate the stylet wire and expand the turns of the lock wire. While thestylet wire is being rotated, the physician secures the position of theproximal end 253 of the lock wire to permit lock wire turns 252 totangle and form a bundle 259 that engages the coiled structure asdepicted in FIG. 8. The stylet may have to rotate 50 to 100 turns toform bundle 259 and engage coiled structure 245.

[0115] After the lock wire has secured the stylet wire to the pacemakerlead, the physician grasps control loop 254 and continues to rotate thestylet wire and pacemaker lead to dislodge anchoring coil 246 from theheart tissue. Should the blood vessels encapsulate the pacemaker lead,separator tube 212 is inserted over the stylet wire and pacemaker leadas previously described to separate the lead from the encapsulatingblood vessel tissue. The separator tube may also be extended to thedistal end of the pacemaker lead to turn and dislodge the distal end ofthe pacemaker lead from the heart tissue.

[0116]FIGS. 32 and 33 depict another embodiment of the lead removalapparatus 3201 of the present invention. Although designated as a leadremoval apparatus, this apparatus can similarly be designated as anextraction device 3201 for removing an implanted lead such as a cardiaclead which has been implanted in biological tissue or, moreparticularly, cardiac tissue. The lead includes a coiled structure 211having a passageway 210 extending longitudinally therein. The leadremoval apparatus comprises a tube 3202 having a longitudinal passageway3218 extending longitudinally therein through which a control means 3203and, in particular, a stylet 3210 extends and is moveable therein. Assuggested, the control means is slidably arranged in the control tube3202 and has a distal end 3204 that is configured for insertion into thepassageway of the coiled structure. The lead removal apparatus alsocomprises expandable means 3205 other than and separate from the controltube and is positioned proximate distal end 3204 of the control means.The expandable means has an expanded position in the passageway of thecoiled structure for securing the control means to the coiled structureand subsequent removal from the biological tissue. The expandable means,or outwardly expandable unit 3205, includes a laterally flexible member3206 that extends longitudinally and proximally from the distal end ofthe control means. This laterally flexible member has a proximal end3207 for assuming an expanded position of the expandable means andengaging the coiled structure. The distal end 3208 of the laterallyflexible member is attached to the control means or style using, forexample, silver solder.

[0117] The lead removal apparatus 3201 further includes a sleeve 3209positioned around the laterally flexible member and the control meansand, in particular, stylet 3210. In the particular embodiment depictedin FIGS. 32 and 33, the distal portion of stylet 3210 is ground to asemicircular shape so as to facilitate insertion in sleeve 3209. Thelaterally flexible member 3206 is formed from the stylet 3210 by foldingthe stylet back on itself about distal end 3204 thereof, forming foldedback portion 3211 of the stylet. The sleeve 3209 and the semicircularshape of the stylet accommodates electrical leads having minimally sizedpassageways 210.

[0118]FIG. 36 depicts an enlarged cross-sectional view of the leadremoval apparatus of FIGS. 32 and 33 taken along the line 36-36. Sleeve3209 comprises a stainless steel cannula of which stylet 3210 andfolded-back portion 3211 are positioned in the passageway thereof. Thesleeve is secured to the folded-back portion and the stylet using, forexample, silver solder as previously suggested.

[0119]FIG. 35 depicts an alternative embodiment of stylet 3210 andfolded-back portion 3211 in sleeve 3209. In this particularconfiguration, the semicircular curved portions of the stylet andfolded-back portion are placed in contact with each other and insertedin the passageway of the sleeve. This particular configuration wouldaccommodate an electrical lead having a larger passageway 210 extendingtherein. Again, stylet 3210 and folded-back portion 3211 are securelypositioned in the passageway of the sleeve using, for example, silversolder 3219.

[0120]FIG. 33 depicts lead removal apparatus 3201 of FIG. 32 in whichexpandable means 3205 is in an expanded position. The lead removalapparatus includes handle 3214 positioned at the proximal end 3215 ofthe stylet 3210 and a handle 3216 positioned at proximal end 3217 ofcontrol tube 3202. As depicted in FIG. 32, the relative longitudinalposition of handles 3214 and 3216 are locked in place using lock 3213such as a pin positioned transversely therethrough. When operating leadremoval apparatus 3201, lock 3213 is removed from the two handles, andhandle 3216 is urged forward in a distal direction with respect tohandle 3214 of the stylet. This causes control tube 3202 to engagelaterally flexible member 3206 and urge laterally flexible member 3206to an expanded position to engage the turns of coiled structure 211.

[0121]FIG. 34 depicts an enlarged view of expandable means 3205 of thelead removal apparatus of FIG. 33. This enlarged view more clearlyindicates that the longitudinal movement of control tube 3202 causes thelateral flexure of laterally flexible member 3206 to engage the turns ofcoiled structure 211. As indicated, proximal end 3207 of the laterallyflexible member is beveled so as to facilitate easy engagement of coiledstructure 211. Furthermore, one or more turns of the coiled structureare engaged between the proximal end 3207 of the laterally flexiblemember and control tube 3202. This engagement provides secure engagementof the laterally flexible member with the coiled structure withoutunduly deforming the coiled structure into passageway 210 of the coiledstructure. As indicated, the engaged turns of the coiled structure arefixed between control tube 3202 and laterally flexible member 3206.

[0122]FIG. 39 depicts an enlarged, partially sectioned side view ofcontrol tube 3202 and stylet 3210 of FIG. 33. Stylet 3210 includes tworight angle bends 3220 and 3221 for engaging the internal walls of thecontrol tube. When control tube 3202 is advanced distally with respectto stylet 3210, these right angle bends help maintain the relativeposition of the control tube and stylet when the control tube isengaging laterally flexible member 3206.

[0123]FIG. 37 depicts an alternative embodiment of control means 3205 oflead removal apparatus 3301 of FIG. 32. Expandable means 3205 oroutwardly expandable unit 3205 includes the distal portion of stylet3210 having a plurality of folded-back portions 3212. The proximal endof the plurality of folded-back portions 3212 forms laterally flexiblemember 3206. As previously suggested, sleeve 3209 is positioned aroundstylet 3210 and the plurality of folded-back portions to maintain thelaterally flexible member in a fixed relative position.

[0124]FIG. 38 depicts an enlarged, cross-sectional view of expandablemeans 3205 of FIG. 37 taken along the line 38-38. This enlarged viewshows that plurality 3212 includes two folded-back portions contained inthe passageway of sleeve 3209 and held in place using silver solder3219. The use of a plurality of folded-back portions allows the use of alarger sleeve and a larger diameter stylet for engaging coiledstructures having a larger passageway 210 than previously described forthe embodiment of FIG. 32.

[0125] FIGS. 40-44 depict alternative embodiments of a lead removalapparatus, such as a locking stylet 510, that comprises a stylet 511, anactuator portion 512, such as an elongate cannula that is slidablydisposed thereover, and an expandable portion 513 attached about thedistal portion 560 of the stylet 511. With the locking stylet 510 havingbeen advanced into the coil of a pacemaker lead (see discussion of FIG.44) such that the expandable portion 513, preferably comprising aplurality of expandable members 514, is situated near the distal tip ofthe pacemaker lead, the actuator portion 512 (also referred to in otherembodiments as the control mechanism) is manually advanced over thestylet 511 until the distal end 539 of the actuator portion 512 contactsthe proximal end 545 of the expandable portion 513. The plurality ofexpandable members 514 plastically or elastically deform as theexpandable portion 513 is longitudinally compressed, at least some ofthem eventually bowing outward until contacting and engaging the coilsof the pacemaker lead. The expandable members 514 provide a positivefixation against and/or between the coils which allows the stylet 511retract the pacemaker lead from the cardiac or scar tissue into which ithas been at least partially ensnared. This positive fixation or bitingengagement in the proximal direction allows the lead to be pulledproximally to allow surrounding tissue to be dilated or removed from theencapsulated lead. Testing has shown that a locking stylet 510 such asthat depicted in FIG. 40 has a pull strength of up to approximately 15pounds, more than sufficient to provide the traction needed to free thelead, absent complicating factors such as extensive formation of scartissue along the length of the lead.

[0126]FIG. 40 depicts an embodiment of the locking stylet 510 in whichthe expandable portion 513 comprises a multifilar wire bundle 515 thatcomprises a series of adjacent windings 570 helically wrapped around thestyle 511 and affixed thereto. In the illustrative embodiment, themultifilar wire bundle 515 includes six individual expandable members514 that comprise helically wound metal wires; however any practicalnumber of wires can be used. It has been found that using a multifilarwire bundle 515, rather than a single helically wound wire, allows forgreater expansion. This results in having a 0.015″ OD locking styletthat can expand to a sufficient diameter to engage and remove thecomplete array of standard pacemaker leads where the range of coil lumendiameters is typically 0.016″ to 0.032″ (approximately 0.4 to 0.9 mm).The term ‘engage’ as used within the portion of the specificationdescribing the embodiments shown in FIGS. 40-47, is defined as asituation in which the expandable members 514 displace, shift, orotherwise intersperse with selected ones of the pacemaker lead coils 548in manner that forms a locking interaction or biting engagment. Thiscontrasts with certain prior art devices in which the interactionbetween the lead removal apparatus and the pacemaker coils is primarilya frictional relationship. As shown in FIG. 41, one method of formingthe multifilar wire bundle 515 is to helically wind the six individualwires 514 together over a pin 541 in the configuration that willultimately be attached distally to the stylet 511. The individual wires514 can be soldered together, if so desired, at their proximal end,which in that case, the pin 541 should be made of titanium or nitinolsuch that the solder will not stick. Once helically wound, themuitifilar wire bundle 515 is inserted over the stylet 511 as shown inFIG. 40. The expandable portion 513 comprising the multifilar wirebundle 515 of the illustrative embodiment is divided into three mainsections. The distal section 517 includes a relatively tight woundwrapping of a multifilar wire bundle 515 that is affixed to the stylet511 about the distal end 516 of the locking stylet 510 with a distalfixation joint 520 such as a solder joint, a crimped band, or some otherwell-known attachment of fixation means. In the intermediate section518, the multifilar wire bundle 515 of the illustrative embodiment iswound more loosely (i.e., with a greater pitch) to permit greaterexpansion during deployment. While the individual wires 514 of themultifilar wire bundle 515 are kept tightly together within the bundle,the gaps 553 between the windings 570 of adjacent multifilar wirebundles 515 increase over that of the distal section 517, in which thegaps 553 are generally minimal (e.g., 0.0035″) to nonexistent. The pitch557 of an individually wound wire 514 can vary within the immediatesection 518, depending on a number of parameters (number of wires, wirediameter, etc.) and the range of expansion desired. In the illustrativeembodiment with an approximately 3″ (7.6 cm) expandable portion thatincludes a six-wire bundle 515 of 0.004″ stainless steel wire, themultifilar wire bundles 515, which measures approximately 0.024″ inwidth, include an increasing pitch 557 toward the center 554 of theintermediate section 518, with a maximum pitch 557 of approximately0.12″. The gaps 553 between the mutlifilar wire bundles 516 becomeprogressively narrower in width toward the proximal half of theintermediate section 518. In the proximal section 519 of theillustrative embodiment, the windings 570 of the mutifilar wire bundle514 include gaps 553 essentially disappear such that the individualbundles 515 are not readily discernable. These dimensions are merelyexemplary and can be varied according to the various structuralparameters selected and the desired performance characteristics of thelead extraction apparatus 510. At the proximal end 545 of the expandableportion 513, a proximal fixation joint 521, such as a silver solderjoint or other bonding means, may be included, however, it is notessential or necessary for the expandable portion 513 to properlyfunction. Unlike the distal fixation joint 521, only the individualwires 514 are soldered together in a proximal fixation joint 521,leaving the expandable portion 513 free to slide over the stylet 511 atthat point. An optional ring, section of cannula, or other structure canbe attached to the proximal end 545 of the expandable portion 513 toprovide a surface against which the actuator portion 512 may contact.

[0127] In the illustrative embodiment, the stylet 511 comprises a0.0075″ 304 stainless steel spring tempered wire with a tensile strengthof 382/455 ksi. The actuator portion 512 comprises a thin wall cannula,such as a 28 gauge hypodermic needle cannula. The length of the actuatorportion 512 is approximately 60 cm from the distal end 539 to the distalhandle 522 to which it is affixed. The wire 514 used is 0.0035-0.004″annealed 304 stainless steel wire. The combination of a 0.0075″ stylet511 and 0.004″ wire 514 yields a device having a 0.0155″ OD, which isabout the practical upper limit if the device is to be used within a0.016″ ID pacemaker coil. If the 0.004″ wire exceeds tolerances, e.g.,more than 0.0002″, the device may not fit within the smaller sizepacemaker lead and one would not have a device that would readily fitwithin the normal range of pacemaker leads sizes.

[0128] The expandable portion 513, being approximately 3 inches long,comprises a distal section 517, intermediate section 518, and proximalsection 518 measuring approximately 0.6″, 2.2″, and 0.3″, respectively.The dimensions of the expandable portion 513 can be quite variable;however, a 3″ length ensures adequate expansion to remove both smallerand larger sized pacemaker leads. The overall length of the lockingstylet in FIG. 40 is approximately 140 cm. As depicted in FIG. 47, theproximal section 519 of the expandable portion 513 can be greatlylengthened and modified to also function as an integral actuator portion512 to compress and expand the intermediate section 518. In thismodification, the actuator portion 512, now a coil of helical wiresrather than a solid cannula, would be integral with the expandableportion 513. Of course, the actuator portion 512 could comprise a coiland still be separate from the expandable member 513 (similar to theembodiment of FIG. 40). Another alternative is for the actuator portionto be a braided tube of metal, plastic, or some other material. In eachof these embodiments, handles 522,523, which are used to facilitateadvancement of the actuator portion 512, and other features shown inFIG. 40 could essentially remain the same as the illustrativeembodiment, if desired.

[0129] As previously noted, the configuration of the expandable portion513 is variable, largely depending on materials of its construction. Itis preferred that the wire 514 be annealed; however, it is possible thatonly a selected portion of the expandable portion 513, e.g., theintermediate section 518, be annealed, or it is possible to havedifferent degrees of annealing across the length of the expandableportion. While the illustrative embodiment utilizes round wire, wireswith alternate cross-sectional geometries (e.g., square, triangular,flattened, etc.) may be used to provide different properties forexpanding and engaging the coils of the lead. Other features could beincorporated such as altering the surface properties of the wire byadding roughness or applying a polymeric coating that could possiblyimproving engagement with the coils. Yet another embodiment would be toinclude wires with different physical properties within a singlemultifilar wire bundle 514.

[0130] Again referring to FIG. 40, an optional feature is depicted inwhich the actuator portion 512 is secured in place to preventadvancement against the expandable portion 513. To accomplish this, theillustrative embodiment includes a deployment guard 534, such as aligature, that is affixed to both the distal handle 522 affixed to theactuator portion 512, and a proximal handle 523 that is affixed to thestylet 511. The distal half 535 of the ligature is secured to theactuator portion 512 with distal knot 526 or other well-known means ofattachment. Optionally, an end of the distal half 535 can extenddistally from the distal end 555 of the distal handle 522 to form anexposed attachment loop 532 to which the physician can tie a suture thatalso is externally secured to the pacemaker lead for providingadditional tractile force. A second knot 572 helps prevent theattachment loop 532 from coming apart when the deployment guard 534 issevered. The distal handle 522 of the illustrative embodiment comprisesa section of shrink wrap 527 that is heat shrunk over the actuatorportion 512 and a section of wrapped wire 540 placed thereover, butunderneath the shrink wrap 527, to advantageously improve the ability ofthe operator to grip the handle 522. Additionally, the shrink wrap 527further secures the distal knot 536. The distal half 535 and theproximal half 536 of the ligature 534 are either joined by, or bisectedby a central knot 537, which in the illustrative embodiment, includes asecond piece of ligature 573 that permits the operator to pull the mainligature 534 away from the stylet 511 to be cut. In the illustrativeembodiment of FIG. 40, the stylet 511 is further protected by a styletguard 542 that represents a proximal extension of the actuator portion512 cannula, which surrounds the otherwise-exposed stylet between thedistal and proximal handles 522,523. This stylet guard 542 can alsocomprise a separate component from the actuator portion 512,particularly in the embodiment of FIG. 47, in which the actuator portion512 and expandable portion 513 are combined. The proximal half 536 ofthe ligature 534 is secured to the stylet 511 using a proximal knot 528.Alternatively, a single piece of ligature can be used, or the ligaturecan be detachable in a manner that does not require that it be severed(i.e., a knot to be untied or another detachable configuration).

[0131] The proximal handle 523 encases the proximal knot 528 and alsoprovides fixation for proximal portion 524 of the handle 523. Theillustrative proximal portion 524 comprises a single twisted length ofwire 556, typically extending at least 30-40 cm, and preferably about60-65 cm, beyond the proximal handle 523 that serves as an extension ofthe stylet 511 and functions much like a handle to allow the operator tocreate traction on the locking stylet 511, such as when placing adilator sheath thereover. In fact, it is conceivable that the stylet 511itself can be extended proximally and actually become the proximalhandle 523 and the proximal portion 524. The proximal portion 524 issized and configured such that it can be manipulated by the operatorwithout requiring the assistance of another individual, while stillenabling the operator to maintain the entire apparatus 510 within thesterile field. In the illustrative embodiment of FIG. 40, the proximalportion 524, which includes an end loop 525 at the proximal end 533 ofthe locking stylet 10, is shown in an uncoiled or straight configuration567. The first end 529 of the twisted wire 556 is laid overlapping thestylet 511, while the second end 530 of the twisted wire 556 is woundaround both, also providing a grip to the proximal handle 523. Afixation joint 531, such as a solder joint, measuring about 0.5″ inlength, secures the two ends, 529,530 and stylet 511 together with theshrink wrap 527 of the proximal handle 523 helping to provide furtherfixation and reinforcement. While the illustrative examples are simplein their construction, it should be noted that distal and proximalhandles 522,523 can assume a wide variety of configurations and beformed from a variety of materials, e.g., molded plastic componentsattached to the actuator portion 512 and stylet 511, respectively.

[0132] The proximal end 538 of the actuator portion 512 extendsproximally to the distal end 557 to the distal handle 522 to protect thestylet 511 when the ligature 534 is cut to allow forward advancement ofthe actuator portion 512. Many possible alternative deployment guards534 for preventing premature forward advancement of the actuator portion512 should be obvious to the skilled artisan. For example, the distaland proximal handles 522,523 can be locked together with a pull pin,adhesive pull strip, or one of a multitude of known fixation means.

[0133] FIGS. 42-43 depict embodiments related to that of FIG. 40. In theembodiment of FIG. 42, the expandable portion 513, comprises expandablemembers 514 that include a plurality 544 of substantially parallel wiresthat are affixed both distally and proximally with fixation joints520,521, such as silver solder. The individual wires 514 bow outward asthe expandable portion 513 is compressed by the advancement of theactuator portion 512, thereby providing an radial expansile force,whereby the expandable members 14 engage the coils of the pacemakerlead. As with the embodiment of FIG. 40, the wire 514 is typicallyannealed, such that it can easily deform to allow the expandable member513 to compress. Alternatively, the wires 514 can be formed with slightkinks or scores within the surface thereof, to facilitate bending duringdeployment.

[0134] The expandable portion 513 depicted in FIG. 43 includes a cannulathat includes a series of longitudinal slots 543 that form a like numberof expandable members 514. As with the embodiments of FIGS. 40 and 42,compression of the expandable member 513 results in deformation of theexpandable members 514 which in turn, contact and engage with the coilsof the pacemaker lead to permit its removal from the patient. Inaddition to having parallel slots 543 as shown, the slots 543 could beof a helical or spiraled configuration. A second inner cannula could beused in conjunction with the first cannula, the second having adifferent configuration of slots to compliment or enhance the functionof the first cannula. It is also possible to combine wound wire with acannula to form the expandable portion 513. It possible to conceive ofan almost unlimited number of different configurations of the expandableportion 513 that would allow a series of expandable members 544 to becompressed via an actuator portion 512 and plastically or elasticallydeformed outwardly to engage the coils of an ensnared lead, therebyassisting in its removal from body tissue. Any such embodiment should beconsidered to fall within the scope of the current invention.

[0135]FIG. 44 depicts the locking stylet 511 of FIG. 40 followingdeployment within a pacemaker lead 546. As the actuator portion 512 isadvanced through the coils 548 of the pacemaker lead 546, over thestylet 511, it contacts the proximal edge 545 of the expandable portion513. Further advancement of the actuator portion 512 forces theexpandable portion 513 to become longitudinally compressed. As theexpandable portion 513 becomes longitudinally compressed, one or more ofthe individual wires 514 comprising the expandable portion 513 will ‘popout’ or kink and extend outward from the mulitfilar bundle 515 andstylet 511 as longitudinal force is applied. As the gaps 553 between thehelical windings 570 narrow and addition wires 514 deform outward, theexpandable portion 513 is compressed further. In a larger sizedpacemaker lead, for example, the expandable portion 513 may becompressed in length from 3″ down to about 0.5″. This causes theunsecured expandable members 544 of the intermediate section 518 tounwind as they plastically deform, thereby expanding outward to contactthe coils 548 and push them outward against the outer insulation 547 ofthe pacemaker lead 546. The expansile force of the expandable members544 often results in the individual wires being pressure into, and somecases, through the spaces 550 between the coil turns, thereby increasingthe fixation between locking stylet 510 and the pacemaker lead 546.Generally, mere frictional engagement between the device 10 and coils548 is not sufficient to allow the lead to be removed from the patientsince the force required typically cannot be achieved before thefrictional engagement fails. The fact that the coils 548 themselves aretypically multifilar, acts to improve the fixation, compared to an leadembodiment having a single coiled electrode wire. As depicted, a section565 of four multifilar coils 548 is generally shifted outward as group,as the wires 514 of the expandable portion apply sufficient force thatparticular section 565. The adjacent section 566, which is not beingimpinged by the expanding wires 514, remains in its original position,thereby creating a ‘shoulder’ at the junction 569 between the twoadjacent sections 565,566, this shoulder facilitating positive fixationof the lead when traction is applied. The actuator portion 512 isadvanced until resistance is met from the expandable portion 513 beingunable to further compress. Depending on the size of the coil lumen 551and the number of wires 512 in the multifilar wire bundle 515, theexpandable members 544 can compress and deform both outward and inwardto form at least one irregular-shaped expanded mass 549 of deformedwires. If the device 510 is being deployed in a smaller lumen pacemakerlead 546, e.g., 0.016″, it requires fewer wires 514 deforming outward tosuccessfully engage the coils 548 and in fact, a large expanded mass 549which is generally required for engaging larger lumen leads, would nothave an opportunity to form given the space limitations. The random andirregular geometry of the protruding wires 514 that eventually comprisethe expanded mass 549 with its twisted bends and interlocking wires,improves fixation compared to expandable members 544 with regular curvedgeometries. The multifilar wire bundle 515 also acts to increase themass needed to fill larger coil lumens which may have up to 4 times thecross-sectional area, thereby permitting one size of locking stylet 510to work for both smaller and larger size coils. The shape of theexpandable mass 549 can vary widely, depending on how it is formed anddeployed. For example, in smaller diameter coil lumens 551, theexpandable portion 513 may form more than one smaller expanded mass 549,rather than one large one. It should be noted that hand winding of themutifilar wire bundles 515 adds to irregularity of the expanded mass 549shape over that which would result from the bundles being machine wound.

[0136]FIG. 46 depicts an embodiment in which the proximal handle 23includes an elongate proximal portion 524 in a pre-shaped or preformedfirst configuration 561 which represents the relaxed state of theproximal portion 524. In the illustrative embodiment, the firstconfiguration 561 is preformed such that the intertwined wire 556comprises a compacted arrangement, such as the illustrative plurality ofcoiled loops 562 (e.g., 3-4). The illustrative first configuration 561conveniently provides the operator an improved configuration forgripping the apparatus 510, such as through the aperture 571 formed bythe loops 562, and more importantly, to be able to maintain the proximalportion 524 in a more compact and manageable configuration to reduce thelikelihood of a portion thereof passing beyond the outer edge 564 ofsterile field 563. Without the compact, pre-shaped configuration 561, asecond person is typically required to hold and maintain the proximalportion 524 within the sterile field 563. As noted, the proximal portion524 is made particularly long, in part, to permit the operator tomanipulate or uncoil the proximal portion 524 into a secondconfiguration 567 (depicted in FIG. 40) which is sufficiently straightto allow a medical device (not shown) having a passageway, such as adilator sheath, to be fed thereover, usually for purposes of assistingin the loosening of scar tissue along the lead path. The proximalportion 524 can either be constrained by operator into the secondconfiguration 567, or it can be done so by feeding the sheath or othermedical device over the proximal portion 524. The first configuration561, as used herein, represents a compacted configuration that includesan overall diameter in its widest plane, including any coils, turns, andbends, that exceeds the passageway diameter of a standard medicaldevice, such as a dilator sheath. The second configuration 267, as usedherein, includes a sufficiently straight configuration (not necessarilybeing substantially straight) such that a standard medical device, suchas a dilator sheath, can be advanced over the proximal portion without alarge degree of difficulty.

[0137] In the embodiment of FIG. 40, the second configuration 267 mayrepresent the relaxed state, in contrast to the embodiment of FIG. 46,which requires manipulation by the operator, to attain a relativelystraightened configuration. Preferably, but not essentially, theproximal portion 524 is designed such that once the medical device haspassed thereover, the proximal portion 524 tends to resiliently returnto the first, compacted configuration 561 by a substantial degree,although it is typical that a certain amount of plastic deformationoccurs such that the original shape is not attained. A substantialreturn to the first configuration 561 allows for a certain,inconsequential amount of plastic deformation. For example, aconfiguration in which the proximal portion 524 includes 3-4 coiledloops 562, may, after being constrained to the second configuration 567,result in a first configuration 561 in which there are 1-2 larger coiledloops 562. In other words, the basic functionality of the firstconfiguration 561 is not significantly compromised by plasticdeformation. By adding shape memory to the proximal portion 524 bywinding the intertwined wire 556 around a fixture to form a series ofcoiled loops 562, the operator can conveniently unwind the proximalportion 524 in a controlled manner and without assistance as the sheathis fed and advanced over the proximal end 533 of the apparatus 510. Itis particularly advantageous to have the proximal end 533 of theapparatus in relative proximity to the point at which the operatorgrasps the apparatus 510, as opposed to having to feed the sheath overthe proximal end 533 of an uncoiled proximal portion 524 that can be50-60 cm or more away, something that at best, is difficult to dowithout allowing a portion of the proximal portion 524 to inadvertentlyleave the sterile field 563 or contact a non-sterile surface. While thepre-shaped configuration 561 of the illustrative embodiment, comprisingcoiled loops 562, represents one preferred embodiment, it should benoted that other pre-formed shapes (e.g., a serpentine configuration)can be fashioned in order to achieve the desired goal, reducing theproximal portion 524 to a manageable configuration that can bemanipulated by a single operation. Additional components may also beincluded, such as clips, housings, etc.) which cooperate with theproximal portion 524 to achieve a compact state, and that still permitpassage of a sheath thereover. Not only does the pre-shaped or coiledproximal portion 524 of the handle 523 have utility in each of theillustrative embodiments, conceivably, any apparatus constructed forremoving elongate structures, such as pacemaker and defibrillator leads,catheters, and the like, can be modified to include a compacted orpre-shaped elongate handle which can function for any of the purposesdescribed above. As used herein, the proximal handle 523 is a commonelement of all lead extraction devices that are manually manipulated byan operator, with the proximal portion 524 being a component thereof forpurposes of nomenclature. The illustrative proximal handle 523 isexemplary, and it should be noted that the proximal handle 523 andproximal portion 524 may represent a common element in some embodiments,especially if the coiled configuration 561 is used as the sole means bywhich the operator grips and applies traction to the apparatus 510.Additionally, the distal handle 522 of the illustrative embodiments ofFIGS. 40-47 is not necessarily present in all embodiments that utilizethe coiled configuration of the proximal handle 523 and proximal portion524, particularly those which lack an actuator portion 512.

[0138] Of course, it will be understood that the aforementioned leadremoval apparatus and method is merely illustrative of the applicationof the principles of this invention and that numerous other arrangementsmay be devised by those skilled in the art without departing from thespirit and scope of the invention. In particular, a number of othercontrol mechanisms may be attached to the proximal end of the styletwire for operating the stylet wire in either a clockwise orcounterclockwise direction as well as moving the wire longitudinally.Furthermore, this apparatus may be utilized for removing electricalleads from body ducts and passages as well as body tissue that hasencapsulated the lead and restricted its movement.

What is claimed is:
 1. A lead removal apparatus for removing animplanted lead from a patient, comprising: a proximal handle locatedabout the proximal end of the apparatus, the proximal handle furthercomprising a elongate proximal portion that is adapted to assume both afirst configuration and a second configuration; wherein the firstconfiguration includes a compacted, pre-formed shape, the proximalportion being constrainable into the second configuration, the secondconfiguration being sufficiently straight in shape to permit passagethereover by a medical device having a passageway extendingtherethrough.
 2. The lead removal apparatus of claim 1, wherein theproximal portion is adapted to at least substantially reassume the firstconfiguration once the proximal portion is no longer being constrainedinto the second configuration.
 3. The lead removal apparatus of claim 1,wherein the first configuration of the proximal portion comprises one ormore coiled loops.
 4. The lead removal apparatus of claim 3, wherein thefirst configuration comprises a plurality of coiled loops.
 5. The leadremoval apparatus of claim 1, wherein the proximal portion has a lengthof about 30 cm or greater.
 6. The lead removal apparatus of claim 5,wherein the proximal portion has a length of about 40 cm or greater. 7.The lead removal apparatus of claim 6, wherein the proximal portion hasa length of about 60 cm or greater.
 8. The lead removal apparatus ofclaim 7, wherein the proximal portion has a length in the range of about60-65 cm.
 9. The lead removal apparatus of claim 1, wherein, theproximal portion comprises a length of intertwined wire.
 10. A leadremoval apparatus for removing an implanted lead from a patient,comprising: a proximal handle located about the proximal end of theapparatus, the proximal handle further comprising a elongate proximalportion that is adapted to assume both a first configuration and asecond configuration; wherein the first configuration includes a one ormore coiled loops having a shape memory, the proximal portion beingconstrainable into the second configuration, the second configurationbeing sufficiently straight in shape to permit passage thereover by amedical device having a passageway extending therethrough.
 11. The leadremoval apparatus of claim 10, wherein the proximal portion is adaptedto at least substantially reassume the first configuration once theproximal portion is no longer being constrained into the secondconfiguration.
 12. The lead removal apparatus of claim 10, wherein thefirst configuration comprises a plurality of coiled loops.
 13. The leadremoval apparatus of claim 10, wherein the proximal portion has a lengthof about 30 cm or greater.
 14. The lead removal apparatus of claim 13,wherein the proximal portion has a length of about 40 cm or greater. 15.The lead removal apparatus of claim 14, wherein the proximal portion hasa length of about 60 cm or greater.
 16. The lead removal apparatus ofclaim 15, wherein the proximal portion has a length in the range ofabout 60-65 cm.
 17. The lead removal apparatus of claim 10, wherein, theproximal portion comprises a length of intertwined wire.
 18. A leadremoval apparatus for removing an implanted lead from a patient,comprising: a proximal handle located about the proximal end of theapparatus, the proximal handle further comprising a elongate proximalportion comprising a length of intertwined wire measuring at least 40cm, the proximal portion adapted to assume both a first configurationand a second configuration; wherein the first configuration includes aplurality of coiled loops having a shape memory, the proximal portionbeing constrainable into the second configuration, the secondconfiguration being sufficiently straight in shape to permit passagethereover by a medical device having a passageway extendingtherethrough; and wherein the proximal portion has a tendency toresiliently reassume the first configuration once the proximal portionis no longer being constrained into the second configuration.